Many persons in the Western Society suffer from neurological diseases like non-AD-dementias, Alzheimer's disease (AD), Parkinson's disease (PD) or Huntington's disease (HD). These diseases are presently diagnosed by a clinician by careful interpretation of a range of symptoms, as defined in the Diagnostic and Statistical Manual of Mental Disorders (fourth Edition, 2000)—DSM-IV-TR) or in McKhann, et al., Report of the NINCDS-ARDA-workgroup, Neurology 1984, 34, 939-944.
Clear differences are observed between persons that suffer from specific types of memory impairment. For example, persons that suffer from Alzheimer's Disease suffer from neurodegeneration, which may be caused by accumulation of amyloid plaques or by neurofibrillary tangles or synaptic loss or atrophy in selected regions in the brain or enlargement of brain ventricles or mixtures of these phenomena. Patients who suffer from vascular dementia suffer from a decreased memory function which has been caused by an impaired cerebral blood flow and the ischemia and reperfusion events. Patients that suffer from dementia with Lewy Bodies or secondary dementias again have a pathology that differs from that of patients who experience the above-mentioned dementias, in terms of the cause, the nature of the damage to the brain and the overall symptoms, though they all demonstrate memory impairment.
In the diagnosis for a dementia, clinicians typically analyse, apart from memory function, at least also other cognitive domains, like ability to execute motor functions, to speak or to recognize objects, ability to function socially and to practice the activities that are considered to be normal in daily living.
Early in aging, in particular in elderly and typically above 60 years of age, mild symptoms of abnormalities in brain function or behaviour sometimes develop. The diffuse pattern of such symptoms may result in the diagnosis by a clinician, based on more or less accepted objective tests that such person suffers from a specific disease state. For example, persons who do not meet certain criteria in memory or cognition tests, but typically perform normal activities in daily life and suffer from no other pathologies, can be diagnosed as persons suffering from “mild cognitive impairment (MCI)”. When the impairment occurs in a more systematic way and is thought to occur due to aging the diagnosis “Age-associated memory impairment” (AAMI) may be made. Some people consider MCI or AAMI as prodromal phase, i.e. a phase prior to but on the way towards the disease, of Alzheimer's disease. However, only less than 25% and in the majority of the cases less than 20% of this group of persons will eventually develop dementias. Part of the group of such “MCI persons” will recover and another part may remain a “MCI patient”.
In this respect, it is submitted that in the context of this application, an elderly person is a person of the age of 50 or more, in particular of the age of 55 or more, more in particular of the age of 60 or more, more in particular of the age of 65 or more. This rather broad definition takes into account the fact that the average age varies between different populations, on different continents, etc. Most developed world countries have accepted the chronological age of 65 years as a definition of ‘elderly’ or older person (associated with the age at which one may begin to receive pension benefits), but like many westernized concepts, this does not adapt well to e.g. the situation in Africa. At the moment, there is no United Nations (UN) standard numerical criterion, but the UN agreed cut-off is 60+ years to refer to the older population in Western world. The more traditional African definitions of an elder or ‘elderly’ person correlate with the chronological ages of 50 to 65 years, depending on the setting, the region and the country.
The distinguishing tests for diagnosing prodromal patients do not coincide with conventional tests for diagnosing dementia or dementia-like disorders, though some of these conventional tests may further support the diagnosis of a prodromal patient for a neurological disorder or disease. For example, prodromal AD patients may score satisfactorily in a memory test, and will therefore not necessarily be MCI patients, whereas they may score positively in the present diagnostic tools for being prodromal. Then the diagnosis “prodromal dementia patient” is made. Such non-MCI group fulfilling the requirements of the diagnosis of a “prodromal dementia patient” has not been addressed by Hansson et al. published in http://neurology.thelancet.com, Feb. 6, 2006. The non-MCI group demonstrating the same score in the proposed tests was not investigated.
Diagnosing a patient as a so-called AAMI or MCI patient will relatively frequently result in false concerns that the patient automatically will become a dementia patient. False positive diagnosis also leads to relatively high costs to the society due to unnecessary measures that are taken to support these patients. Therefore a need exists to develop better diagnostic tools to identify the various types of brain diseases or disorders which may occur in a person during aging and to identify the prognosis, which belongs to a specific preclinical phase. Also a need exists to support the unique group of prodromal dementia patients, to decrease the likelihood that they will develop a form of senile dementia.
WO 2007/008586 discloses a method to reduce the level of amyloid beta peptide in an individual comprising administering a source of docosahexaenoic acid and docosa-pentaenoic acid ω-6. WO 2006/031683 discloses the use of a uridine, preferably in combination with choline for improving a cognitive or neurological function. WO 2006/127620 discloses a composition comprising DHA and UMP for the treatment of a subject with a memory disorder, learning problems, or a neurological disorder, such as an Alzheimer patient. Wurtman et al., Brain Research 2006, 1088(1), 83-92 disclose a combination of choline, UMP and DHA being able to enhance the quantity of synaptic proteins and phospholipids in gerbil brains and being potentially useful in treating Alzheimer's disease. WO 03/041701 discloses a composition comprising DHA, EPA, choline, methionine, vitamin B6, folic acid, zinc, magnesium and UMP as alternative for nucleobases for the treatment of Parkinson's disease, epilepsy, schizophrenia, paranoia, depression, sleep disorders, psychoses, dementia, ADHA, impaired memory function, chronic fatigue syndrome and motoric disorders.
However, nowhere in the art a suggestion has been made to use these fractions for the treatment of prodromal dementia patients, which have specific lesions in the neuro-logical system, for example in the brain or experience specific biochemical pathologies.